A picture can contain GPS coordinates in its metadata. Open the photo details to see whether it shows a location. Keep a private original if location helps you organize your photo library.
Prepare the file
On iPhone, choose Share in Photos and look for Options. Turn Location off before sharing if the option is available. On a computer, export a copy from a photo editor with location metadata excluded. On Windows, you can check a JPEG in Properties, under Details, and use Remove Properties and Personal Information when available.
Check the finished copy
Inspect the actual exported file in a photo information viewer before uploading. Check the visible picture too. A street sign, address label or recognizable building can reveal a location even when the GPS fields are gone.